Differentiating benign from malignant gallbladder wall thickening in non-contrast MRI imaging: Preliminary study of a combined diagnostic indicator.

To synthetically evaluate the diagnostic accuracy of image features for differentiating benign from malignant gallbladder wall thickening disease with non-contrast MRI and establish the optimal diagnostic indicator. A total of 23 patients with wall thickening type gallbladder carcinoma and 61 patients with benign wall thickening disease were included. The diagnostic performance of six image features including the layered pattern on T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) images, T2WI signal intensity, papillary growth, the apparent diffusion coefficient (ADC) value, and the lesion to liver parenchyma ratio (LLR) of gallbladder were evaluated and compared. The receiver operating characteristic (ROC) curve and binary logistic regression analysis were used to construct the optimally combined indicator. All six indicators showed high diagnostic accuracy. The layered pattern on DWI and LLR had the highest area under the curve (AUC) value (0.904), followed by the layered pattern on T2WI (0.883), T2WI signal intensity (0.859), ADC value (0.836), and papillary growth (0.796). There was no statistically significant difference in the AUC among indicators for pairwise comparisons. A combination of layered patterns on DWI and papillary growth was shown to be the optimal indicator by binary logistic regression analysis. The AUC value of the combination (0.972) was higher than the layered pattern on DWI (0.904) and papillary growth (0.796) (P < .001). Non-contrast MRI provides several reliable indicators for differentiating benign from malignant gallbladder thickening disease. The combination of layered patterns on DWI and papillary growth is the optimal indicator.

[Application value of multiple phase subtraction imaging of dynamic contrast enhanced magnetic resonance imaging in common breast tumor].

OBJECTIVE: To evaluate the application value of multiple phase subtraction imaging of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in common breast tumor. METHODS: All radiographic and MRI data of 72 patients with histological proved common breast tumor were analyzed retrospectively. Prior to an injection of gadolinium-diethylenetriaminepentaacetate (GD-DTPA), 3D mask scans were performed. Then 9 consecutive phases of imaging were acquired. After the drawing of time-signal intensity curve, he first and second phases were selected to perform subtraction with the mask, rebuild 3D maximum intensity projection and analyze the application value of subtracted and 3D maximum intensity projection (MIP) reformation images. Chi-square test was used for the analyses of benign and malignant breast tumors. RESULTS: There were 83 lesions in 72 patients. Among 18 cases of fibro adenoma, 23 lesions had no tumor vessel. For the detecting ratio of lesions, the first and second phase subtraction imaging had no statistics difference. Only one intraductal papilloma with ductal carcinoma in situ (DCIS) had tumor vessel in 4 intraductal papilloma patients. Among 5 DCIS cases, one of them had small curved tumor vessel. And 51 lesions were found in 45 infiltrating ductal carcinoma (IDC) cases. Tumor vessels could be seen in all IDC cases. And 37 cases had multiple tumor vessels while 8 cases had single tumor vessel. When the first phase was used for subtraction, 36 lesions were found. On the other hand, 51 lesions were found in the second phase subtraction. There were significant differences between them. CONCLUSION: No significant differences exist in benign breast tumor on differential phase subtraction images of DCE-MRI, but there are significant differences in malignant breast tumor. It is very important to detect the lesions and show the tumor vessels by rebuilding multiple phase subtraction.